Can I share files (e.g. .bib and some graphics) across my projects?

Yes, you can do this using the “Include file from other project” option within the Add Files menu:

One convenient way to set this up if you're planning to use the same files across mulitple projects is to organize things as follows:

1. Create a “master” project containing your common files e.g. .bib, .cls, .sty, graphics, etc.
2. In your “child” projects, click the “Upload files” button at the top of the file list panel.
3. Select “From another project project”, and navigate to your “master” project, and select the file that you need.

You will now be able to used the linked file in your “child” project.

If you’ve modified the original copy of the files in the “master” project, remember to click on the linked file in the “child” projects and then “Refresh” to pull in the changes.